Air conditioning apparatus



y 1964 w. 1.. MCGRATH AIR CONDITIONING APPARATUS Filed 001. 11. 1957 OUTDOOR COIL INDOOR CO! INVENTOR.

WILLIAM L.MCGRATH BY J ATToRN EY United States Patent 3,132,492 AIR CGNDETIONING APPARATUS William L. McGrath, Syracuse, N.Y., assignor to Carrier Corporation, Syracuse, N.Y., a corporation of Delaware Filed Get. 11, 1957, Scr. No. 689,676 J 8 Claims. (Cl. 62324) This invention relates to air conditioning and more particularly to an improved heat pump operable under the reverse cycle principle to provide heating, cooling, or dehumidification.

It is the chief object of the present invention to pro-- vide an air conditioning system which provides cooling, heating, or dehumidification while utilizing a minimum of components. Other objectsand attendant advantages of the present invention will readily be perceived hereafter.

The present invention relates to air conditioning apparatus for selectively providing heating, cooling, or dehumdification comprising a compressor, a plurality of first heat exchange coils normally located indoors, a plurality of second heat exchange coils normally located outdoors, a plurality of expansion members, each coupling one of said first coils to one of said secondcoils to provide separate continuous refrigerant circuits, and

a plurality of reversing valves, each coupling a first coil and a second coil of each circuit to said compressor to permit said first coils to selectively produce heating, cooling, or dehumidification. The present invention will be more fully understood when the following portions of the specification are read in conjunction with the accompanying drawing.

The figure shows in diagrammatic form, the circuit of the air conditioning apparatus.

A compressor 10 has suction line 11-12 and discharge lines 13 and 14 coupled thereto. Afour-way valve 15 of conventional construction is associated with conduits 11 and 13. When valve 15 is in the position shown, compressed refrigerant is passed through conduit 16 thereof toheat exchange coil 17 of heat exchanger 18 which is normally located out of doors. Refrigerant then passes through conduit 19 and expansion member 20 to heat exchange section 21 of indoor coil 22 and then through conduit 23 and conduit 24 of four-way valve 15 to suction line 11 of the compressor10;

Another four-way valve 25 of conventional construction is coupled to conduits 11-42 and 14. When fourway valve 25 is in the position shown in the drawing, compressed refrigerant passes from compressor 10 through discharge line 14 and conduit 26 of valve 25 to heat exchange coil section 27 of outdoor coil 18. Refrigerant then passes through conduit28 and expansion member 29 "to heat exchange coil section 30 of indoor coil 22 and then through conduit 31, conduit 32 of valve 25 and conduit 11-42 to the suction side of compressor ltl.

When four-way valves 15 and 25 are in the position tions as an evaporator to cool air passing therethrough to thus condense moisture in the air. Indoorcoil section 21, however, functions as a condenser to reheat the air which has been chilled because of its passage in heat exchange relation with coil 36. In this manner dehumidification with reheat is obtained. i

It will be noticed, however, that the heat exchange sections 17 and 27 of outdoor coil 18 are intertwined. When valves 15 and 25 are placed in thedehumidification position, coil section 17 functions as an evaporator and coil section 27 functions as a condenser. The cooling produced by coil section 17 causes optimum condensation of refrigerant in coil section 27; thus, coil section 39 can operate at a lower temperature and thus perform more efiicient dehumidification.

As can be seen from the drawing, fans 33 and 34- are provided for causing air flow over the outdoor coil 18 and indoor coil 34 respectively. As mentioned above, on the dehumidification'cycle, air to be conditioned flows in the direction of the arrows over coil 30 which functions as an evaporator and then over coil 21 which functions as a condenser.

It will readily be appreciated that heat exchange coil 18 which has been designated an outdoor coil is normally placed out-of-doors, whereas coil 22 is placed within the area to be conditioned. However, if it should be so desired, heat exchange coil 18 may be placed in contact with a Water source so that it extracts heat from the water source upon the heating cycle and is water-cooled by the water source onthe cooling cycle.

It will be seen that I have provided air conditioning apparatus which can selectively provide heating, cooling, or dehumidification in a simple, efficient and inexpensive manner, in that it utilizes a minimum number of parts and makes most efiicient use of those parts which are employed.

While I have described a preferred embodiment of my invention, I desire it to be understood that it may be otherwise embodied within the scope of the following claims.

I claim:

1. Air conditioning apparatus for selectively providing heating, cooling,'or dehumidification comprising a compressor, a plurality of first heat exchange coils, a plurality of second heat exchange coils, a plurality of expansion members each coupling one of said first coils to one of said second coils to provide separate continuous refrigerant circuits, and valve means associated with each pair of coils coupling a first coil and a second coil of each circuit to said compressor to permit said first coils to selectively produce heating,.cooling, or dehumidification.

2. Air conditioning apparatus as set forth in claim 1 wherein said valve means include four-way valves.

shown in the drawing, sections 17 and 27 of outdoor coil 18 function as condensers and sections 21 and 30 of indoor coil 22 function as evaporators.

When it is desired to place the air conditioning system on the heating cycle, reversing valves 15 and 25 are manipulated so asyto cause the conduits therein to assume their dotted line positions.

Under these circumstances, indoor coil section 30 func- When this is done, the refrigerant flow in both circuits is reversed so that coil sections 21 and 30 of indoor coil 22 function as con- In this manner indoor coil 22 3. Air conditioning apparatus as set forth in claim 1 wherein said first coils are positioned next to each other to permit air to pass first over one coil and then over the other coil.

4. Air conditioning apparatus as set forth in claim 3 wherein said first coils are so positioned with respect to the conditioned air stream soas to permit dehumidifying and heating of said air stream.

5. Air conditioning apparatus as set forth in claim 4 wherein said second coils are intertwined.

6 In air conditioning apparatus including a com pression refrigeration system, a compressor, first and second indoor heat exchangers-,first and second outdoor.

heat exchangers, means providing a first refrigerant flow path from said compressor through said first outdoor heat exchanger to said first indoor heat exchanger and back to said compressor, and means including areversing valve providing a second refrigerant flow path parallel to said first refrigerant flow path and adapted to selectively direct refrigerant from said compressor through said second outdoor heat exchanger to said second indoor heat exchanger or through said second indoor heat exchanger to said second outdoor heat exchanger, whereby heat is selectively absorbed in one of said second heat exchangers and dissipated by the other of said second heat exchangers.

7. In air conditioning apparatus including a compression refrigeration system, a compressor having an inlet and an outlet, an indoor heat exchanger, an outdoor heat exchanger, means including a bidirectional expansion device connecting said outdoor heat exchanger to said indoor heat exchanger and permitting refrigerant flow in either direction from one to the other of said heat exchangers, means including a reversing valve for selectively connecting the outlet of said compressor to said outdoor heat exchanger and the inlet of said compressor to said indoor heat exchanger or the outlet of said com pressor to said indoor heat exchanger and the inlet of said compressor to said outdoor heat exchanger, an evaporator, a condenser, means connecting said compressor, condenser, and evaporator for routing refrigerant from said compressor through said condenser to said evaporator regardless of the condition of said reversing valve, means for circulating indoor air over said indoor heat exchanger and said evaporator, and means for circulating outdoor air over said outdoor heat exchanger and said condenser.

8. In a refrigeration circuit for air conditioning apparatus, a compressor having an inlet and an outlet, first and second indoor heat exchangers, first and second outdoor heat exchangers, means including an expansion device connecting the first outdoor heat exchanger to the first indoor heat exchanger, conduit means connecting the outlet of said compressor to said first outdoor heat exchanger and the inlet of said compressor to said first indoor heat exchanger, means including a bidirectional expansion device connecting said second outdoor heat exchanger to said secondindoor heat exchanger and permitting refrigerant to flow in either direction from one to the other of said second heat exchangers, and means including a reversing valve for selectively connecting the outlet of said compressor to said second outdoor heat exchanger and the inlet of said compressor to said second indoor heat exchanger or the outlet of said compressor to said second indoor heat exchanger and the inlet of the compressor to said second outdoor heat exchanger.

2,376,859 Benn May 29, 1945 

1. AIR CONDITIONING APPARATUS FOR SELECTIVELY PROVIDING HEATING, COOLING, OR DEHUMIDIFICATION COMPRISING A COMPRESSOR, A PLURALITY OF FIRST HEAT EXCHANGE COILS, A PLURALITY OF SECOND HEAT EXCHANGE COILS, A PLURALITY OF EXPANSION MEMBERS EACH COUPLING ONE OF SAID FIRST COILS TO ONE OF SAID SECOND COILS TO PROVIDE SEPARATE CONTINUOUS REFRIGERANT CIRCUITS, AND VALVE MEANS ASSOCIATED WITH EACH PAIR OF COILS COUPLING A FIRST COIL AND A SECOND COIL OF EACH CIRCUIT TO SAID COMPRESSOR TO PERMIT SAID FIRST COILS TO SELECTIVELY PRODUCE HEATING, COOLING, OR DEHUMIDIFICATION. 